Expected return rate determined as oriented fuzzy number

The starting point for our discussion is the present value (PV) determined by means of positive L-R fuzzy number. In this paper the information described by the so-determined PV is supplemented with a subjective forecast of the sense trend of observed current market price. This forecast is implemented in the proposed PV model, as the orientation of fuzzy number. The assumption of market price increase is described as a positive orientation of ordered fuzzy number. In analogous way, the assumption of market price decrease is described as the negative orientation of ordered fuzzy number. In this way, PV is presented as ordered fuzzy number [2]. So specified PV is used for determine the return rate which is defined as any decreasing function of PV and increasing function of future value (FV). With the obvious assumption that the FV is a random variable, determined return rate is described as ordered fuzzy random variable. At the end it is shown that the expected return rate is determined as ordered fuzzy number. The orientation of expected return rate is opposite to orientation of the PV defining it.